Login Redirect Multisite

I'm trying to configure Login Redirect for multisite so when a user registers his blog and login he goes directly to

blah.com/newblog/wp-admin/themes

But how I configure this with Login Redirect?

If I put /wp-admin/themes in the network settings, create a test blog and then login it gives me a message saying the user tried to access the main site dashboard.

Can you please help?